Phonographic apparatus



Se t. 21, 1937. j E. D. COOK 93,

PHONOGRAPHIG APPARATUS a Filed Dec. 30, 1933 2 Sheets-Sheet 1 as 8 e 1415 15 31 16 a V 13 J a 65 a a i 1 1 o 4 1 INVENTOE': v ElLYPI/t/D.Cfolofif,

Patented Sept. 21,1937

PHONOGRAPHIC APPARATUS Ellsworth n. Cook,.Mercliantville, N. J.,assignor to Radio Corporation of America, a corporation of DelawareApplication December 30, 1933, Serial No. 704,605

21 Claims.

This invention relates to phonographic apparatus, and more particularlyto soundrecording and sound reproducing apparatus of the type subject tothe serious disadvantages that both the'records and needles employedsuffer considerable wear which renders them unfit for further use aftera comparatively short life and the further disadvantage that the drag ofthe needle over the record introduces foreign noises which areobjectionable.

According to the other system, the sound isrecorded photographically,most generally-upon a long strip of sensitized film which, duringreproduction, is run through the reproducing apparatus from one reelonto another. While this system is free from some of the disadvantagesof the first system, it is, nevertheless, subject to some that are justas serious as those above noted. For example, a film phonograph,regardless of its simplicity, has an element of complexity about itsthreading. Moreover, such a phonograph includes a multiplicity of partssuch as a film guide or support at the reproducing station, pressurerollers, film reels, etc. for the film itself, it must constantly bewound on and unwound from the reels and, being usually fed by sprocketsthe teeth of which engage the sprocket hole perforations, is subject togreat wear and tearing, the latter necessitating patching, splicing,etc. and involving considerable servicing. Another disadvantage of thissystem is that the film is subject to scratching and marring duringhandling and during passagethrough the reproducer, all of whichintroduce obnoxious foreign noises. Also,'the duplication of recordsfrom lon films necessitates complicated machinery and processing, andall of the foregoing have in no small way mitigated against theuniversal adoption of the photographic system of recording andreproducing sound.

In order to eliminate some of the difficulties noted above, it'has beenproposed to record the sound photographically, in the form of anuninterrwted spiral. upon- ;a sensitized circular disc or plain. So. faras I am aware, however,

prior art systems of this type have employed complicated devices forscanning the sound track. For example lead screws and the like have beenemployed to movethe optical system, light source, and photoelectricdevice used in reproduction 5 radially across the record. Not only is aconstruction of this sort cumbersome, but it is difficult to set up andcontrol accurately. Also, with such set-ups of the prior art, it isextremely difficult, if not altogether impossible, to make provision forthe continued repetition of a record or any preselected portionsthereof, or for the reproduction of one record and the immediatereproduction of a second, and perhaps unrelated, record, with animmediate return to the first 5 record or to another record uponcompletion of the second one, as might be required in special uses ofthe' phonograph, such as. in advertisin announcing, etc. Where, as in a.few cases, repeat mechanisms may have been provided, they have been bothcomplicated and expensive.

The primary object of my invention is 'toprovide a photophonographicapparatus of the disc type which will be free from the disadvantages ofthe prior art and which is so'constructed and arranged that it will beflexible in its uses and will, therefore, meet practically everyreasonable requirement of sound reproducing apparatus. v

Another object of my invention isto provide an improved apparatus ofthis type which will include a minimum number of movable parts and whichwill, therefore, be free from unusual and unnecessary wear.

I Still another object of my invention is to provide an improvedapparatus of the type noted which can be set to repeat any preselectedportions' of a record with practically no additional mechanismover thatrequired in reproduction.

It is another object of my invention to provide an approved apparatus ofthis type by means of 40 which a plurality of records may be reproducedeither serially or.simultaneously,=as may be desired.

A further object of my invention is to provide an improved apparatus ofthe type set forth in which the light beam, although maintainedstationary, is, nevertheless, rendered eflective at that portion of thesound track which it is desired to reproduce and at that portion only.

Still a further object of my invention is u to provide an improvedapparatus of the type men'- tloned in which cross talk, or thesimultaneous reproduction of two adjacent. lines of the spiral, isentirely eliminated.

Another object of my invention ist'o provide 7 the accompanyingdrawings, in which a novel scanning system aforementioned type.

It is also an object of my invention to provide a method by, which theproper location of the 5 scanning means with respect to the record. isinsured. 1 And a further object of my invention isto provide improvedapparatus of the type noted heretofore which will be exceedingly simplein, construction and extremely simple in operation, which can bemanufactured without necessity of observing fine tolerances, and whichis not only very efllcient in operation, but also extremely versatile inthe results which it can produce.

According to my inventio'n,,I provide, in a phonograph. employing arecord on which the sound is recorded in the form of an Archimedian'spiral track, a stationary light source and optical system which focusesa fine line of light radially across the record so. as to include allthe spirals or turns across one radius. On the other side of the record,a stationary photo-electric cell is disposed, the active element of thecell havinga length equal'to the length of the radial light line andbeing:in alignment therewith. In order to mask oif all the light exceptthat desired at the reproducing point, an opaque mask provided with anArchimedian, transparent spiral is placed adjacent the record sothat thespiral record track and the spiral in the maskwill have thesamegeometrical center. The ac- 1 tion will bereadily understood uponconsidering the equation of ,an Archimedian spiral. It will be notedthat'the derivative in the radial 35 directionis constant, that is, therate of radius change is constant'throughout the length of such aspiral. Taking advantage of this fact, -it is possible to choose atleast one such curve which, when rotated at some definite speed, will4ointersect another concentric Archimedian spiral rotated at some otherspeed along certain fl'xed lines'in' space lying in the plane of thespirals and passing through their common center. Now, if the line oflight mentioned above is located at 45 one of these fixed lines, thatportion of the line of light which will pass through both the -scanningmask and the record, and thus will reach the photo-electric cell, mustmove in a radial direction with a velocity equal to that of the recordspirals for 'app ratus of the in the same direction. By proper choice ofthe .60 number of scanning spirals-and by thecircumferentialdisplacement and pitch of these spirals,

while the control of the system to reproduce any preselected portion orportions of the record may be eflected for example, by control of theexciter lamp circuit.

The novel features that I consider characteristic of my invention areset forth with particularity in the appended claims. Theinvention-itself,

0 however, both as to its organization and method I of operation,togetherwith additional objects and advantages thereof, will best beunderstood from thefollowing description of several specific embodimentsthereof, when read in connection with Figure l is a centr sectional viewof one form of my improved apparatus,

Figure 2 is a plan view showing the relation of the record and thescanning mask, the record having a single spiral sound track thereon andthe scanning mask having two scanning spirals thereon,

Figure 3 is a view similar to Figure 2 but showing the double-spiralscanning mask applied to a record having two sound tracks thereon,

Figure 4 is a perspective view of the reproducmg optical system and itsrelation to thellght source,

Figure 5 is aside pr end elevation of a similar optical systemarrangedfor recording, I

Figure 6 is a view, partly in perspective and partly diagrammaticillustrating one method of controlling the motor to stop it at apredetermined point in the record, and Figure 7 is a view similar toFigure 6 but showing one method of controlling the light source filamentcircuit to insure-reproduction of,

onlya preselected portion of the record.

' Referring, first, to Figure 1, there is shown a motor plate I on whichis supported a motor 2 which drives a spindle 3 having a gear 4 fixedthereto. The gear I meshes with and drives a gear I to which is staked agear 6 mounted for rotation on a stub shaft 1, the gear 6 meshing withand driving a gear 8 fixed to a sleeve 9 the celving poi-tion If at theupper end thereof beyond a flange portion. II which acts as a recordsupporting turntable and lies in substantially the same plane as theflange III. The sleeve I! may be locked to the spindle ii in anysuitable manner for rotation therewith. In the particular embodimentillustrated, the spindle 3 is split at its upper end and is internallythreaded below the split portion to receive a screw l5 having awedgeshape head. As the screw I5 is screwed down,

'the wedge head expands the split portion of the spindle, therebylocking in place a record It su ported on the flange i4.

The record It may'comprise a disc of any suitable base, such as glass,celluloid, 'etc. coated with a photosensitive emulsion in which a soundtrack II has been recorded, the sound track being in the form of anArchimedian spiral of comparatively flne pitch and having, preferably,the same geometrical center as the disc itself. Mounted on the flange I0is a disc of opaque material I! having one or more Archimedian spiralscanningtracks is formed therein. By way of example, ,I have shown thescanning disc I. as provided with two such spiral scanning tracks evenlyspacedfromeach other circumferentially, but any,. number of scanningtracks may be employed as will appear more clearly hereinafter.

The scanning disc It may be formed ot some suitable opaque material suchas metal, fd'r example, in which case the scanning tracks I 9 may be cutout or punched out therefrom to' form trans- 4 parent spiral scanningslots. The scanning 1180' It may, however, also be made of aphotosensitized base similar to that ofthe record, with the scanningtracks recorded therein. In any case,

however, the scanning tracks I9 are made of a much coarser pitch thanthat of the sound tracks I! and are also formed with their geometricalcenters preferably coinciding with that of the disc I8.

The scanning disc I8 is mounted 0n the flange or turntable I0 and isfixed thereto by means of a pin 20, the axis of the scanning tracks I9being in alignment with that of the spindle 3. The record I8, asexplained heretofore, is supported on the turntable I4 with the axis ofthe sound track II also in alignment with that of the spindle 3. Thus,the tracks I1 and I9 all have a common geometrical center when mountedon the phonograph for operation. The record I6 is also so mounted withrespect to the scanning disc I8 that the beginning of the sound track IIis in alignment with, or coincides with, the beginning of one of thespiral scanning tracks I9. For this purpose, the record I6 may beperforated with several apertures, each-along a different radius fromthe center of therecord.

When the record I6 is placed on the turntable I4, these apertures aremade to fit over a'corresponding number of pins 2| upstanding from theturntable I4, the position of each of the apertures andtheir'corresponding pins 2I being so chosen that the record I6 can onlybe mounted in operative position and locked to the turntable I4 when thebeginning of the sound track I1 is in alignment with the beginning ofone of the scanning tracks I9.

Fixed to the bracket 22 supported by the motor plate I is a casing 23which houses a light source and associated optical system for focusingupon the record I6 a thin line of light radially thereacross and of sucha length as to cover allof the turns of the sound track spiral along theradius. The light source may comprise a straight coiled filament 24(Figure 4) and the optical system a pair of cylindrical lenses 25 and26. The lens 25 is disposed in close proximity to the filament 24 andhas its axis at right angles to that of the filament, serving as acondenser to produce a beam of minimum divergence after I leaving thelens. A mask 21 may be provided to assist in limiting the fieldor areailluminated by the light passed through the lens 25. The lens 28 isplaced as close to the record 16 as practical with its axis paralleltothat of the filament 24,

and this lens serves to focus upon the record I6,

in the plane thereof, the coil diameter of the filament 24. In thismanner, maximum use is made of the light source and a fine or thin lineof light 28 is focused upon the record I6 across the sound track spiralI I.

Disposed beneath the scanning disc I8 in alignment with the light line28 is a photoelectric cell 38 having an active element at least as longas the light line 28 itself. Light passing through the record ismodulated thereby and affects the photoelectric cell to cause it to setup varying currents representative of the sound being reproduced. Thescanning disc I8 being opaque except at the scanning tracks I9, itisapparent that light can pass through both the record I6 andthescanning disc I8 at only those portions where the sound track I1 andthe scanning tracks I9 cross each other. Now, if the light line 28 isfocused upon the record in a position such that it intersects the soundtrack I1 and one of the scanning tracks I9 at the same point where thesetwo tracks intersect each other, light will pass through both the recordI6 and the scanning disc I8 at such point and at no other points.

Let it be assumed that the point where the sound track I1, the scanningtrack I9 and the light line 28 all intersect each other is at thebeginning of the sound track, as shown in Figure 2, the scanning spiralsI9 being in the start position designated S. As the record I6 rotates inthe direction of the arrow, the spiral sound an angle such that thescanning track I9 under the light line 28 will also have moved along thelight line the same radial distance, namely a distance equal tothe pitchof the sound track spiral. In other words, for one revolution of thesound record after starting reproduction, the scanning disc will havemoved from starting position S to the position P, in which the activescanning track I9 will intersect ,the beginning of the second turn ofthe spiral sound track I! immediately under the light line 28, and solong as this relation is maintained between the respective rotary speedsof the record and the scanning disc, the sound track I! and itscooperating scanning track I9 will move along the fixed light line 28 inoverlapping or intersecting relation at the sound line. That'is to say,as long as'the aforesaid condition is maintained, the sound track I1 andone of the scanning tracks I9 will always intersect each other at somepoint on the light Iine28. It is for this reason that the sleeve 9 andthe hollow shaft I2 are so geared together that the former rotates at amuch slower speed than the latter.

The speed of rotation of the scanning disc l8 relative to that of therecord I6 is determined by two factors, namely, the relative pitches ofthe sound track I1 and the scanning tracks I9, and the number ofscanning tracks I9 on the disc I8. If the speed of the record is (9),for example, and the number of sound track spirals to be scanned is (y)then the speed of the scanning disc must equal and the pitch of thescanning spiral must be (y) times that of the sound track. Now, if thescanning disc is provided with (n) evenly spaced scanning spirals in onecircumference of the scan-' ning mask, it is clear that, for a recordspeed (0), the scanning disc must .rotate at a speed speed of the soundrecord and that of the scanning disc, and in this way the activescanning spiral I9 and the sound track I! are made to travel uniformlyinwardly along the fixed light line 28 in properly intersectingrelation.

By proper choice of records having a plurality of sound tracks thereonand corresponding scan- 5 ning discs, it is possible to employ thepresent invention for either the simultaneous reproduction of all thesound tracks or for successive reproduction thereof. For the sake ofsimplicity, suppose it is desired to reproduce either or both of tworecords recorded on the disc l5. Ob-

viously, a portion of the radius could be allotted to each record andtwo scanning spirals of proper pitch could be located to embrace onlythese portions of the allotted radius. By the use of separatephotoelectric cells, either record could be played individually or bothrecords could be played simultaneously, depending, for example, onwhether one or both photoelectric cells are energized. The opticalsystem could be made to cover both records simultaneously, although, ifdesired, independent optical systems could be used for each record andthe light source associated with each optical system controlled foreither separate or simultaneous reproduction. 2 The same results can beaccomplished by providing the record IS with two concentric spiraltracks l1 and |'|a as in Figure 3, each having twice the pitch of thesound track I! of Figure 2, and both starting on the same diameter butat points on the circumference of the record 180 apart. For the sake ofsimplicity, I have shown a scanning disc having two spiral scanningtracks l9 and |9a associated with the record of Figure 3, the scanningtrack l9 cooperating with the sound track I! and the scanning track |9acooperating with the sound track IIa. Like the sound tracks I1 and ||a,the scanning spirals I9 .and |9a are concentric and also start. on thesame diameter but 180 apart circumferentially of the scanning disc Hi.The speed of the disc l8 must, in this case, be such that the completerecord is played by one scanning track during half a revolution of thescanning disc and is repeated by the other scanning track during thenext half revolution of the disc |8. By providing two optical systems tofocus two light lines 28 and 28a onto the record IS on opposite sides ofthe record center but on the samediameter and two photoelectric cells,the two .sound tracks can be reproduced either simultaneously orseparately, as desired.

It is also possible to employ my improved phonograph to effect thetiming and occurrence of a certain number of events to synchronize withthe record. For the sake of simplicity, and by way of example, I haveshown, in Figures 6 and '7, how the stopping of the phonograph at apredetermined point may be eifected or how only preselected portions ofa record may be. reproduced. Referring to Figure 6, I have shown acontrol ring 3| of conducting material which may be fixed to the gear 8to rotate at the same speed as the scanning disc l8, the ring 3| beingprovided with an insulating block 32 at its periphery.

A pair of brushes 33 and 34 connected in series with the motor 2 and asource of current supply 'contact the periphery of the ring 3| andcomplete the circuit to the motor therethrough. When, however, theinsulating block 32 slides under the brush 34, the motor circuit isbroken and. the phonograph stops its operation. The block 32 may be setin the ring 3| at such a point, for example, that the phonograph willautomatically stop at the completion of reproduction of a record andwith the beginning of the scanning track I9 in alignment with thebeginning of the sound track I! at the light line 28. A switch 36connected across the brushes 33 and 34 may be used to start thephonograph again,

or by maintaining the switch 36 constantly closed,

continuous operation is assured. Obviously, instead of controlling themotor, the ring 3| may be employed to control the operation of any otherdevice to cause the occurrence of some event related to the record.

In Figure 7, I have shown one method of effecting reproduction of onlya. preselected portion of a record. A control ring 4| similar to thering 3| but stepped to provide two peripheral portions 42 and 43 isprovided with a pair of insulating switch actuating members 44 and 45,the former on the periphery 42 and the latter on the periphery 43. Thefilament coil 24 is connected to a suitable source of current supplythrough a pair of switch contacts 46 adapted to be bridged by a contactmember 41 the position of which is determined by a pair of relays 48 and49. The relay 48 is connected to a source of current 50 through a masterswitch 5| and a spring blade switch 52 located in the path of travel ofthe actuating member 44, while the relay 49 is similarly connected tothe source 50 through a master switch 53 and a spring blade switch 54located in the path of travel of the actuating member 45.

As long as the motor 2 is energized, the ring 4|, being fixed to thegear 8, for example, will continue to rotate indefinitely in thedirection of the arrow and at the speed of the scanning disc I 8. Withthe switch 5| closed, when the actuating member 44 rides under the bladeof switch 52, the latter switch is closed momentarily whereupon therelay 48 is energized to move the contact member 41 into the solid lineposition of Figure 7, thus completing the circuit to the filament 24 andcausing it to glow. The relays 48 and 49 may be holding relays or thecontact member 41 may be of the toggle type. In either event, however,when the relay 48 has moved the contact member 41 to the solid lineposition, the contact member 41 will remain there and the filament 24will continue to glow. With the ring 4| rotating in the direction ofthe'arrow, the actuating member 45 will eventually close the switch 54.As soon as this occurs, the relay 49 is momentarily energized whereuponthe contact member 41 is moved to; and held in the dotted line positionof Figure '7. This breaks the circuit'of the filament 24 andreproduction stops. Thus, between the time that the actuating member 45closes the switch 54 and the time that the actuating member 44 closesthe switch 52, the filament 24 is not energized and therefore noreproduction takes place. By making the actuating members 44 and 45respectively adjustable on the peripheries 42 and 43, the silent periodcan be controlled to omit any undesired portions of the record and,therefore, the phonograph set to reproduce only the preselected portionof the record. Also, by opening the switches 5| and 53, the controldevice may be rendered ineffective, and in] such case, the contactmember 41 may be operated manually. As in the case of the control systemof Figure 6, that of Figure 7 may be employed to control the occurrenceof any desired events or the operation of apparatus other than thefilament 24 at a predetermined time and in synchronism with the record.

When it is desired to record sound, the re.- producer may be readilyconverted into a regrammatically at'60 in Fig. and may comprise like.

any one of the various forms of light valves ,well

known in the prior art, as, for example, a Kerr I .cell, a pair ofrelatively movable shutters, or the The scanning disc 3 should then, ofcourse, be on the same side of the record as the optical system. i

Although I have shownand described several embodiments of my invention,it will be apparent to 'those'skilled in the art that many changestherein and modifications thereof are possible without departing fromthe spirit thereof. For example, instead of mounting-the record abovethe scanning disc, the latter maybe mounted above the record, as shownin Figure 5. However, I prefer the construction shown in Figure 1, sinceit is usually necessary'to change only the records. Mounting the recordabove the scanning disc permits making the scanning disc a permanentpartof the apparatus, if desired. Many other changes will undoubtedlyreadily suggest themselvesto those skilled in the art. My invention,therefore, is not to be limited except insofar as is necessitated by theprior art and 'bythe spirit of the appended claims;

I claim as my invention:

1. In phonographic apparatus, the combination of a rotatable discrecord, a rotatable record scanning member associated with said record,and a fixed optical system adapted to direct light toward said recordand said scanning member.

2. In phonographic apparatus, the combina-' track thereon, andascanningmember'associated Archimedian spirals of different pitches. 5.The invention set forth in claim 3 whereinthe sound track and thescanning track are both Archimedian spirals and wherein the scanningtrack spiral has a greater pitch than the sound track spiral.

6. The invention set forth in claim 3 wherein the sound track and thescanning track are both Archimedian spirals and-wherein the record andthe scanning member are so .associated that the sound track'spiral andthe scanning track spiral have a common geometrical center.

7. The invention set forth in claim 3 characterized in that the scanningmember is associated with the record in a predetermined relation andcharacterized further by the addition of means for maintaining therecord andthe scanning member in said relation. 1

8. In photo-phonographic apparatus, a sound record, means for scanningsaid sound record, said sound record and scanning means being both Imovable relative to eachother, means for providing a. stationary lightbeam in cooperative relation to said record and said scanning means,

and means for maintaining said record and said scanning means inv apredetermined movable relation to each other with respect to, said'light beam.

9. In photo-phonographic apparatus, the combination of a movable recordhaving a spiral sound track thereon, an opaque scanning memberassociated with said record and movable relativefthereto, said scanningmember being providedwith a transparent spiral scanning track, a lightsource, means for projecting from said light source a thin line of lightradially across said sound track, and means for maintaining.

said.sound record and said scanning member in such relation that saidspiral sound track and said spiral scanning track'will always intersecteach other at some point on said line of light.

10. In photo-phonographic apparatus, the combination of .a pair ofconcentric turntables, one of said turntables being annular andsurrounding the other, a sound record supported on one of saidturntables, said sound record having an Archimedian spiral sound trackthereon,

an opaque scanning member provided with an Archimedian, transparent,spiral scanning track, the pitch of'said scanning track being greaterthan the pitch of said sound track, said scansource a; thin line oflight radially across said record, means for mounting said record onsaid first named turntable in a predetermined relation to said scanningmember such that said sound track, said scanning track and said line oflight all intersect at a poi t, means for r0- tating said record at apredetermined rotary speed, and means for rotating said scanning memberat such a rotary-speed relative to said record that said spiral scanningtrack will always intersect said sound track along said light line.

' 11. In photo-phonographic apparatus, the combination of a sound recordhaving a plurality of sound tracks thereon, and a scanning memberassociated with said record, said scanning member having at least onescanning track for each of said sound. tracks and being mounted formovement simultaneously with said record, and said scanning tracks beingeach adapted to scan the' entire length oftheir respectively associatedsound tracks.

12. In photo-phonographic apparatus, l the combination of amovable soundrecord having a sound track thereon, and a'scanning member associatedwith and movable relative to said record,

said scanning member having a plurality of sound track thereon, and ascanning memberasv sociated with and rotatable relative to said record,said scanning member being provided with a spiral scanning track ofgreater pitchthanthe pitch of said sound track, and the speed ofrotation of said scanning member relative to that of the sound recordbeing a function of the relative V pitch dimensions of said respectivetracks.

14:. In photo-acoustic' apparatus, the combina- I tion of arotatablesound record having a spiral sound track thereon, and ascanning member associated with and rotatablerelative to saidiec- 0rd,said scanning member being pr'ovided with a plurality of spiral scanningtracks evenly spaced on said scanning member.

\ 15. In vphonographic apparatus, a sound record, means for reproducingsound from said record,- and means external to the record for renderingsaid sound reproducing means ineffective to reproduce sound betweenpredetermined points insaid record. f k 16. In photo-phonographicapparatus, a photographic record, a light source adapted to cooperate thsaid record to reproduce sound, an energizing circuit for said lightsauce, and means external to said record for maintaining said circuitclosed between predetermined points in said record and open betweenother predetermined points in said record. f

17. Inph'oto-phonographic apparatus, a rotatable record having a spiralsound track thereon, a scanning member associated with said rec-- 0rdand rotatable relative; thereto, said scanning member having a spiralscanning track of greater 1 pitch than said sound track for scanningsaid sound track, a motor for driving said record and said scanningmember, and meansYor controlling said motor to cause it tostop when saidscanning a I member has reached a predetermined position relative tosaid record. v

18. In photo-phonographic apparatus, a rotatable record having a spiralsound track thereon, a scanning member associated with said rec- 19minphoto-acoustical apparatus, means for illuminating a photographicrecordpsaid means comprising a filamentary light source, a cylindricalcondensing lens in close proximity to the filament of said light sourcewith the axis oi said lensat right angles to that of said filament, and20 a second cylindricallens in close proximity to the record, saidsecond lens having its axis parallel to that of said filament x 20..Imphoto-acoustical apparatus, means for il-.

'luminat'ing a photographic record, said means comprising a light sourceincluding a coiled filament optical condensing means adjacent saidfilament tor projecting toward said record a light beam of minimumdivergence, and optical means' adjacent the record for focusing uponsaid record,

in the plane the'reof,'-the filament coil diameter.

21pm phonographic apparatus, the'combination of a sound record, andscanning means therefor substa ially co-extensive with the entire areaotsaid rd. ELL SWOR'I'H D. COOK.

